/**
 * Copyright (c) 2021 OceanBase
 * OceanBase CE is licensed under Mulan PubL v2.
 * You can use this software according to the terms and conditions of the Mulan PubL v2.
 * You may obtain a copy of Mulan PubL v2 at:
 *          http://license.coscl.org.cn/MulanPubL-2.0
 * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
 * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
 * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
 * See the Mulan PubL v2 for more details.
 */

#ifndef OCEANBASE_SQL_ENGINE_EXPR_FORMAT_H_
#define OCEANBASE_SQL_ENGINE_EXPR_FORMAT_H_

#include "sql/engine/expr/ob_expr_operator.h"

namespace oceanbase {
namespace sql {

class ObLocale {
  public:
  uint decimal_point_;
  uint thousand_sep_;
  const char* grouping_;
  ObLocale()
      : decimal_point_('.'), /* decimal point en_US */
        thousand_sep_(','),  /* thousands_sep en_US */
        grouping_("\x03\x03")
  {} /* grouping en_US */
  ObLocale(uint decimal_point_par, uint thousand_sep_par, const char* grouping_par)
      : decimal_point_(decimal_point_par), thousand_sep_(thousand_sep_par), grouping_(grouping_par)
  {}
};

class ObExprFormat : public ObFuncExprOperator {
  public:
  explicit ObExprFormat(common::ObIAllocator& alloc);
  virtual ~ObExprFormat();
  virtual int calc_result_typeN(
      ObExprResType& type, ObExprResType* types, int64_t param_num, common::ObExprTypeCtx& type_ctx) const;
  virtual int calc_resultN(
      common::ObObj& result, const common::ObObj* objs_array, int64_t param_num, common::ObExprCtx& expr_ctx) const;
  virtual int cg_expr(ObExprCGCtx& expr_cg_ctx, const ObRawExpr& raw_expr, ObExpr& rt_expr) const override;
  static int calc_format_expr(const ObExpr& expr, ObEvalCtx& ctx, ObDatum& res_datum);

  private:
  int get_origin_param_type(ObExprResType& ori_type) const;
  int convert_num_to_str(
      const common::ObObj* objs_array, common::ObExprCtx& expr_ctx, int64_t scale, common::ObString& num_str) const;
  static int64_t get_format_scale(int64_t scale);
  static int convert_num_to_str(const common::ObObjType& obj_type, const ObDatum& x_datum, char* buf, int64_t buf_len,
      int64_t scale, common::ObString& num_str);
  static int build_format_str(char* buf, const ObLocale& locale, int64_t scale, common::ObString& num_str);
  int calc_result_type(ObExprResType& type, ObExprResType* types) const;
  DISALLOW_COPY_AND_ASSIGN(ObExprFormat);
};
}  // namespace sql
}  // namespace oceanbase

#endif /* OCEANBASE_SQL_ENGINE_EXPR_CHAR_H_ */
